Sociodemographic and clinical profile of attempted suicide patients

Introduction

Suicide attempts are common and constitute a serious problem for public health.Thus, it is very important to evaluate risk factors for suicidal behavior.

Objectives

The purpose of this study was to explore the socio-demographic and clinical profile of attempted suicide patients consulting in the psychiatry department in Gabes (southern of Tunisia).

Methods

It was a retrospective descriptive and analytical study covering all patients who had attempted suicide during the period from the 1st of May, 2009 to September 25th, 2020 and who were referred to the psychiatry department in the regional hospital of Gabes. Sociodemographic and clinical data of the patients as well as characteristics of the suicide attemptswere assessed.

Results

Socio-demographic profile of the suicidal consultant in psychiatry department corresponded to a single (73.4%) female (78.8%), with a mean age of 26 years, from an urban area (46%). Suicide attempts were most often by the intentional drug ingestion (67.8%), committed between March and August in 54% of cases. At most of the time, the suicidal person was alone (85%) at home (94%) when he committed his suicidal attempt. He did not communicate his intention to commit suicide in 46% of the cases and only 22 cases (7.9%) notified a person before the suicide attempt and 12.6% afterwards. Suicide behavior was impulsive in 79.5% of the cases and a verbal expression of a desire to die was only noted in 24.5% of cases.

Conclusions

Our results suggest a systematic and specific psychiatric evaluation of any patient who attempts suicide.

Conflict of interest

No significant relationships.

Socio-demographic and clinical features of patients with dementia attended in the psychiatry department

Introduction

Dementia’s prevalence increases due to population aging, it has become a major public health concern.

Objectives

To estimate the incidence of dementia and to describe the socio-demographic and clinical profile of patients attended in the psychiatry department of Gabes (Southern of Tunisia).

Methods

It was a retrospective descriptive study including all the patients who attended for the first time in the psychiatry department of Gabes, from the 1st January, 2010 to December 31, 2018, and who were diagnosed with dementia according to the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV). Socio-demographic and clinical data were assessed. The Mini Mental State Examination (MMSE) was used as a neuropsychological examination.

Results

We included 98 patients. The mean annual hospital incidence of dementia was 2.38%. The mean age was 76.5 ± 9.8 years. Patients were married (68%), illiterate (68%) and jobless (42.9%). A family history of dementia was noted in 39.8% of patients. The common cardiovascular comorbidity was high blood pressure (41.8%). Among our patients, 30 (30.6%) were smokers. The mean age of onset of dementia was 73 ± 11 years. The mean duration of untreated dementia was 3 years [3 months to 11 years]. First symptoms were mainly memory disorders (57.3 %) and behavioral disorders (17.3%) The mean MMSE score was 14 ± 4.8. Alzheimer’s disease was the most frequent etiology of dementia (80 cases, 82.7%).

Conclusions

Our study shows a high incidence of dementia and made it possible to draw up a socio-demographic and clinical profile of dementia patients.

Disclosure

No significant relationships.

Vaginismus: Sociodemographic profile and cultural aspects

Introduction

Vaginismus is the most common reason for unconsummated marriages in Tunisia.

Objectives

To describe the socio-demographic profile and to explore the clinical and cultural aspects of sexual functioning of women with vaginismus.

Methods

It was a cross-sectional study established over a period of 3 months from the November 1st, 2019 to January 31st, 2020. This study focused on a population of women with vaginismus recruited from outpatient consultations of the hospital’s gynecology and psychiatry departments at the regional hospital of Gabes. We used a pre-established sheet exploring socio-demographic data, medical and gyneco-obstetric history and informations concerning the partner, the marital relationship and the woman’s sexual activity.

Results

35 women were included. They had a mean age of 30 years, jobless (54.5%) and with a secondary or university education (91.1%). The mean duration of marriage was 2.4 years. Partner had mean age of 36 and suffering from sexual dysfunction (21.3%). Among women, 12.5% had been sexually abused, 51.6% had suffered “Tasfih”, 70% had attended discussions about painful defloration. Vaginismus was primary in 85.7% and total in 50% of the cases. About the received thoughts of the women, 40% thought that vaginismus requires medical treatment, 13 of them (40%) thought that the disorder could be resolved spontaneously and 20% believed in a story of witchcraft. 85% consulted a physician and 24.2% a traditional therapist.

Conclusions

Vaginismus seems to be influenced by psychological and sociocultural factors so that a good psychoeducation of brides could reduce the incidence of this sexual disorder.

Conflict of interest

No significant relationships.

Warning signs of suicide attempts and risk of suicidal recurrence

Introduction

Detecting warning signs of suicide attempts is a particular difficult task. However, people who plan to commit suicide almost always announce it to someone in some way.

Objectives

Aims of this study were to describe signs preceding the suicide attempt in a group of suicidal persons and its links with suicidal recurrence.

Methods

It was a retrospective study that included all the patients who attempted suicide during the period from May 1st, 2009 to September 25th, 2020 and who were referred to the psychiatry department of the regional hospital of Gabes. Sociodemographic and clinical data as well as suicidal attempts characteristics were assessed.

Results

278 patients were included (female=78.1%), with mean age of 26. The common suicidal attempt method was intentional drug intoxication (67.8%). At least, one clinical manifestation was reported by 75.2% of suicide patients. The most common signs were the tendency to isolation (47.1%), a change in character or behavior (46.6%), thoughts of death (29.6%), anxiety or agitation (24.8%) and recent worsening of the pre-existing psychiatric symptoms (24.3%). Suicidal recurrence affected 24.8% of patients. It was correlated to the presence of a mental disorder (p<10-3), the presence of reflections on death (p=0.02), the onset of a state of anxiety or agitation (p<10-3), recent worsening of pre-existing psychiatric symptoms (p = 0.001) and verbal expression of suicidal thoughts (p<10-3).

Conclusions

The pre-suicidal syndrome is frequently heralded by changes in the patient’s character or behavior. Some suicidal warning signs are associated with the risk of suicidal recurrence.

Conflict of interest

No significant relationships.

Covid19 pandemic impacts on mental health of tunisian health care workers

Introduction

Covid19 pandemic in Tunisia has disturbed the health system. Health care workers, who were in the frontline to face this disease, had experienced reactions of anxiety, depression and distress.

Objectives

To assess the level of anxiety and depression among health care workers of regional hospital of Gabes (south of Tunisia) and its associated factors.

Methods

We conducted a cross-sectional study, from April 19, 2020, to May 5, 2020 on healthcare workers in Gabes regional Hospital. All hospital departments and units were included. We used a self-administered anonymous questionnaire containing sociodemographic and clinical data. Hospital Anxiety and Depression Scale (HAD) validated in the Tunisian dialectal version was used to assess anxiety and depression.

Results

Among the 289 responding participants, 100 (34.6%) were frontline health care workers directly engaged in managing patients with coronavirus disease. Our study revealed that 43.6% of health care workers were suffering from anxiety and 44.3 % from depression. There was a significant association between anxiety and female gender (p<0.001), being married (p=0.006), mental health conditions (p<0.001) especially anxiety disorders (p<0.001) and depressive disorders (p=0.03), personal medical history of dysthyroidism (p=0.013) and smoking (p=0.005). Nurses experienced more likely anxiety symptoms than other occupation (p=0.021). There was significant relationship between depression and female gender (p<0.001), married status (p=0.02), age under 50 (p=0.032) and mental health conditions (p<0.001) such as anxiety disorders (p=0.001) and depressive disorders (p=0.013).

Conclusions

It is crucial to provide care for health care workers with mental health problems during their struggle with covid19.

Sleep disorders among health care workers practicing in emergency department in south tunisia

Introduction

Sleep disorders are the most common health problem among the health care staff, mainly those who perform night shifts.

Objectives

To assess the prevalence of sleep disorders among health care workers in emergency department and to determine its associated factors.

Methods

It was a cross-sectional study, including health care workers assigned to emergency ward and intensive care unit of Hedi Chaker and Habib Bourguiba hospitals in Sfax and regional hospital of Kebili, during the first six months of 2017. We used an anonymous and confidential self-administered questionnaire. We used hospital anxiety and depression scale (HAD) to assess anxiety and depression. Sleep quality was assessed by the Pittsburgh Sleep Quality Index and day time sleepiness by the Epworth Sleepiness Scale.

Results

240 nurses were included. Mean age was 37 years-old, 59.2% were female and 64.2% were married and 79.2% assured night shifts. The prevalence of sleep disorders was 70.4%. Sleep difficulties were significantly correlated with anxiety (p=0.001) and depression (p=0.02). In multivariate study, sleep disorders were related to the absence of leisure activity (OR=0.42 [0.19-0.94]; p=0.035) and anxiety (OR=3 [1.4-6.1]; p=0.002). 40.8% of nurses experienced drowsiness. Sleepiness was significantly correlated with the absence of leisure activities (p=0.04) and with psychiatric family history (p=0.02). In the multivariate study, sleep disorders were correlated with female gender (OR=0.43 [0.19-0.9]; p=0.042) and with no leisure activity (OR=2.6 [1.2-5.6]; p=0.01).

Conclusions

Sleep disorders were common among emergency nurses, in order of that; working conditions should be improved to provide less stressful conditions for nurses.

Conflict of interest

No significant relationships.

Standardized risk management in catheterization procedures for non-ST-segment elevation myocardial infarction: associations with in-hospital clinical outcomes

Introduction and purpose

Patient risk in non-ST-segment elevation myocardial infarction (NSTEMI) depends on clinical setting, individual patient variables and procedural characteristics. Standardized risk-adjusted periprocedural management for catheterization procedures using a Standard Operating Procedure (SOP) was investigated to evaluate associations with in-hospital clinical outcomes.

Methods

In 01/2018, our heart center established an SOP for coronary catheterization procedures in NSTEMI, targeting 1) standardized pre-procedural risk assessment using National Cardiovascular Data Registry (NCDR) risk models, and 2) standardized post-procedural risk-adjusted safety measures, including advanced patient monitoring (intermediate/intensive care) and use of vascular closure devices. All patients presenting with invasively-managed NSTEMI in 2018 were retrospectively evaluated for SOP-based pre-procedural risk scoring, SOP-based post-procedural management and in-hospital clinical outcomes of mortality, major bleeding (MB, according to BARC ≥3) and acute kidney injury (AKI, according to KDIGO).

Results

A total of 430 patients (age 72±12 years, 71% male, BMI 27±5) presenting with NSTEMI from 01 to 12/2018 were included, 9.8% presented in cardiogenic shock and 4.7% had suffered a preclinical cardiac arrest. Overall in-hospital mortality was 3.7%, MB occurred in 6.5%. 207 patients (48.1%, SOP+ group) had received both 1) pre-procedural risk assessment and 2) post-procedural risk-adjusted safety measures; the other 223 patients (51.9%, SOP- group) had not received either 1) or 2). There were no significant differences in baseline characteristics and prior-existing medical conditions between groups, however, significantly more patients in SOP- group were treated in emergency settings (39.9% vs. 21.7%, p=0.004). However, significantly more patients in SOP- were treated in emergency settings at higher risk (39.9% (SOP-) vs. 21.7% (SOP+); p&lt;0.001). In univariate analysis, all in-hospital clinical outcomes of mortality (1.4% (SOP+) vs. 5.8% (SOP-); p=0.016), MB (2.9% (SOP+) vs. 9.9% (SOP-); p=0.003) and AKI were significantly lower in the SOP+ group (15.9% (SOP+) vs. 24.2% (SOP-); p=0.033). After correction for the difference in risk between groups due to emergency settings by multivariate logistic regression analysis, MB remained significantly lower in SOP+ (p=0.02), while mortality (p=0.14) and AKI (p=0.19) were not significantly associated with SOP-status anymore.

Conclusion

Standardized risk management in invasively managed NSTEMI was associated with significantly lower rates of in-hospital major bleedings.

Funding Acknowledgement

Type of funding source: Private grant(s) and/or Sponsorship. Main funding source(s): Junior Clinician Scientist Track, Medical faculty, Heinrich-Heine-University Düsseldorf, Germany

Targeting Tumor Cells with Anti-CD44 Antibody Triggers Macrophage-Mediated Immune Modulatory Effects in a Cancer Xenograft Model

CD44, a transmembrane receptor reported to be involved in various cellular functions, is overexpressed in several cancer types and supposed to be involved in the initiation, progression and prognosis of these cancers. Since the sequence of events following the blockage of the CD44-HA interaction has not yet been studied in detail, we profiled xenograft tumors by RNA Sequencing to elucidate the mode of action of the anti-CD44 antibody RG7356. Analysis of tumor and host gene-expression profiles led us to the hypothesis that treatment with RG7356 antibody leads to an activation of the immune system. Using cytokine measurements we further show that this activation involves the secretion of chemo-attractants necessary for the recruitment of immune cells (i.e. macrophages) to the tumor site. We finally provide evidence for antibody-dependent cellular phagocytosis (ADCP) of the malignant cells by macrophages.

Abstract 3631: Whole transcriptome and exome targeted RNA sequencing for FFPE tumor samples from clinical trials

Currently there are multiple approaches for measuring gene expression from human tissue samples on the market. These methods range from measuring the expression of a few genes using quantitative RT-PCR to measuring every gene in a sample by whole transcriptome RNA sequencing (RNA-Seq). Although many techniques and products for measuring gene expression are available, the highly degraded RNA isolated from formalin-fixed, paraffin embedded (FFPE) tumor tissues still poses a challenge for many of them. FFPE tumor samples are an abundant source of biomarker information and gene expression analysis in these samples has the potential to identify new signatures, biomarkers, or diagnostics that could predict patient response to treatment. Accurately measuring gene expression in a high throughput manner from this sample type has long been a struggle in the field.

To determine the ability of RNA-Seq to accurately measure gene expression from FFPE-derived RNA, we utilized a large collection of matched fresh frozen (FF) and FFPE samples from 12 different tumor indications. By comparing the results to the matching FF sample, we were able to determine the accuracy and sensitivity of each platform when using degraded FFPE-derived RNA. The FFPE samples in the collection had a wide range of RNA quality scores (RIN score: 0-6.8, DV200:0-78) representing what is typically isolated from clinical trial samples.

We further compared whole transcriptome RNA-Seq with a hybrid capture method, RNA Access, to determine the accuracy and feasibility of using this technology on degraded RNA. RNA Access selects for protein coding transcripts by hybridization, whereas whole transcriptome RNA-seq removes ribosomal RNA, but analyzes everything else i.e. the global transcriptome. All samples were sequenced to an average of 50 or 25 million paired-end reads for whole transcriptome RNA-Seq and RNA Access, respectively and 100 ng of RNA was used as input in both assays.

We conclude that both methods can be used for analyzing FFPE tumor samples. A similar dynamic range was observed for both methods and both show similar correlation between FF and FFPE samples within the method (0.76 vs 0.74). The overall concordance between methods was 0.69 and 0.63 for FF and FFPE, respectively. When looking specifically at the detection of 90 low expressing immune related genes, both assays were able to detect &gt;94% with an inter-platform correlation of 0.66 and 0.56 in FF and FFPE, respectively.

Whole transcriptome RNA-seq provides the maximum amount of information from clinical samples including anti-sense and non-coding RNA detection while RNA Access can be applied more cost-efficiently when one is mostly interested in the protein coding transcriptome.

Citation Format: Erica B. Schleifman, Anna Kiialainen, Andreas Roller, Sabine Bader, Maipelo Motlhabi, Priti Hegde, Ian McCaffery, Garret Hampton, Michael Cannarile, Craig Cummings, Olivia Spleiss, Eric Peters. Whole transcriptome and exome targeted RNA sequencing for FFPE tumor samples from clinical trials. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 3631.

Abstract 952: Induction of avidity-driven hyperclustering of DR5 by a new FAP-DR5 bispecific antibody (RG7386) leads to strong anti-tumor efficacy

Background:

Activation of the extrinsic apoptotic pathway by TRAIL is dependent on clustering of death receptors (DR) on the surface of cells. However, current TRAIL-based strategies have proven ineffective in clustering death receptors and failed to demonstrate robust therapeutic activity in clinical trials. More potent DR agonist therapies could help to overcome insufficient pathway activation and resistance to TRAIL activation. RG7386 is a novel bispecific FAP-DR5 antibody, binding with high affinity to fibroblast activation protein (FAP) and with low affinity to DR5. FAP is expressed at high prevalence on cancer associated fibroblasts (CAFs) in various tumor types as well as on tumors of mesenchymal origin, such as sarcomas. Avidity-driven binding of the bispecific antibody induces hyperclustering of DR5, which leads to potent induction of extrinsic apoptosis pathway signaling and tumor cell death. Biomarkers will be crucial in predicting sensitivity to DR5 activation and apoptosis induction and for selection of patients most likely to benefit from treatment with RG7386.

Aim:

The aim of the study was to explore the efficacy of RG7386 in vitro and in vivo. CRC and PDAC xenograft models expressing FAP on tumor stroma as well as sarcoma models were used to explore in vivo efficacy. Molecular profiling of sensitive and resistant tumors was also performed to identify response prediction markers.

Results:

RG7386 demonstrated additive efficacy in vitro with clinically relevant combinations (e.g. irinotecan, paclitaxel) in a variety of CRC and PDAC cell lines. In a xenograft model, where CRC cells (DLD-1) were co-injected with fibroblasts, RG7386 showed strong anti-tumor efficacy in combination with irinotecan. Remarkably, in a patient-derived CRC xenograft model (Co5896), the efficacy of RG7386 in combination with irinotecan induced complete tumor remission in all mice (n = 10/10). Furthermore, the combination of RG7386 with doxorubicin generated complete remissions in FAP+ sarcoma patient and desmoplastic melanoma cell line derived xenograft models such as Sarc4605 and LOX-IMVI. Finally, extensive molecular profiling of sensitive and resistance models in vitro revealed a distinct response prediction signature of DR5 sensitivity.

Conclusion:

RG7386 is a novel bispecific antibody inducing avidity-driven DR5 crosslinking by binding to FAP. This induces potent apoptosis of tumor cells, making it an attractive therapeutic approach for treatment of FAP+ solid tumors. Encouraging data indicate the high potential of RG7386 to treat FAP positive sarcomas. A comprehensive biomarker program will be employed in the early clinical development of RG7386 to enable selection of patients likely to benefit and to corroborate the mode of action, anti-tumor activity and potential response prediction markers.

Citation Format: Thomas Friess, Stefanie Lechner, Esther Abraham, Ann-Marie Broeske, Sabine Bader, Andreas Roller, Meher Majety, Katharina Wartha, Suzana Vega-Harring, Hadassah Sade, Oliver Krieter, Peter Bruenker. Induction of avidity-driven hyperclustering of DR5 by a new FAP-DR5 bispecific antibody (RG7386) leads to strong anti-tumor efficacy. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 952. doi:10.1158/1538-7445.AM2015-952

Abstract 2835: MDM2 antagonist-based therapeutic response is discriminated by a 4-gene signature in acute myeloid leukemia patients

The activity of p53, a key tumor suppressor is tightly controlled by MDM2-mediated ubiquination and degradation. Nutlins, a class of small-molecule MDM2 antagonists, have been characterized as drivers of p53 re-activation. Acute myeloid leukemia (AML) is uniquely sensitive to p53 re-activation as ∼90% of cases have wild-type TP53 and frequent MDM2 overexpression to overcome mechanisms of oncogene addiction. Personalized theranostic strategies may distinguish patients likely to clinically benefit from MDM2-antagonist therapy.

Association between MDM2 antagonist (RG7112) growth inhibition (IC50s) in 287 human cancer cell lines (Cell Lines for Oncology/Chugai Accumulative Tumor Encyclopedia), and pretreatment RNAseq profiling established a classifier comprising MDM2, XPC, BBC3, and CDKN2A. This signature significantly associated with cell-line efficacy to MDM2 antagonist (odds ratio = 2.53; P&lt;0.001) and discriminated MDM2 antagonist-sensitive (IC50 10 uM) better than MDM2 mRNA or TP53 mutation status alone (AUC = 0.92). Multivariate logistic regression indicated signature scores were significant (odds ratio = 1.84; P&lt;0.001) when adjusted for TP53 mutation status.

RG7112 treatment was assessed in a phase 1 dose escalation trial in relapsed/refractory AML patients (NO21279). Signature scores of AML patient blood specimens at baseline significantly associated with clinical response (PD&lt;HI&lt;MLFS&lt;CR; Spearman correlation coefficient 0.58; P&lt;0.001); and with pharmacodynamic biomarker response, defined as change in MDM2 mRNA expression in blood (Spearman correlation coefficient 0.41; P = 0.02). Patient response was discriminated by the signature with 100% sensitivity/71% specificity (Wilcoxon p = .0007, AUC = 0.72). Monitoring of signature with clinical response in a second AML Phase 1/1b clinical trial NP28679 with a next generation nutlin-class MDM2 Antagonist RG7388 validated this panel as significantly discriminating MDM2 antagonist therapeutic responders and non-responders in AML patients (Wilcoxon Rank Sum Test P = 0.008; AUC = .75).

In summary, we demonstrate that a biological classifier discriminates response broadly to MDM2-antagonist therapy. The level of evidence attained by cell line efficacy modeling and response assessments in trial NO21279 (with MDM2 antagonist RG7112) and now in trial NP28679 (with MDM2 antagonist RG7388) adds substantial weight to the validity of this panel.

Citation Format: Hua Zhong, Gong Chen, Lori Jukofsky, David Geho, Sung Won Han, Fabian Birzele, Sabine Bader, Lucia Himmelein, James Cai, Zayed Albertyn, Mark Rothe, Laurent Essioux, Helmut Burtscher, Steven A. Middleton, Lin-Chi Chen, Markus Dangl, William E. Pierceall, Gwen Nichols. MDM2 antagonist-based therapeutic response is discriminated by a 4-gene signature in acute myeloid leukemia patients. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2835. doi:10.1158/1538-7445.AM2015-2835

Evaluation of Protein Profiles From Treated Xenograft Tumor Models Identifies an Antibody Panel for Formalin-fixed and Paraffin-embedded (FFPE) Tissue Analysis by Reverse Phase Protein Arrays (RPPA)

Reverse phase protein arrays (RPPA) are an established tool for measuring the expression and activation status of multiple proteins in parallel using only very small amounts of tissue. Several studies have demonstrated the value of this technique for signaling pathway analysis using proteins extracted from fresh frozen (FF) tissue in line with validated antibodies for this tissue type; however, formalin fixation and paraffin embedding (FFPE) is the standard method for tissue preservation in the clinical setting. Hence, we performed RPPA to measure profiles for a set of 300 protein markers using matched FF and FFPE tissue specimens to identify which markers performed similarly using the RPPA technique in fixed and unfixed tissues. Protein lysates were prepared from matched FF and FFPE tissue specimens of individual tumors taken from three different xenograft models of human cancer. Materials from both untreated mice and mice treated with either anti-HER3 or bispecific anti-IGF-1R/EGFR monoclonal antibodies were analyzed. Correlations between signals from FF and FFPE tissue samples were investigated. Overall, 60 markers were identified that produced comparable profiles between FF and FFPE tissues, demonstrating significant correlation between the two sample types. The top 25 markers also showed significance after correction for multiple testing. The panel of markers covered several clinically relevant tumor signaling pathways and both phosphorylated and nonphosphorylated proteins were represented. Biologically relevant changes in marker expression were noted when RPPA profiles from treated and untreated xenografts were compared. These data demonstrate that, using appropriately selected antibodies, RPPA analysis from FFPE tissue is well feasible and generates biologically meaningful information. The identified panel of markers that generate similar profiles in matched fixed and unfixed tissue samples may be clinically useful for pharmacodynamic studies of drug effect using FFPE tissues.

Evaluation of efficacy of a new MEK inhibitor, RO4987655, in human tumor xenografts by [(18)F] FDG-PET imaging combined with proteomic approaches

BACKGROUND

Inhibition of mitogen-activated protein kinase (MEK, also known as MAPK2, MAPKK), a key molecule of the Ras/MAPK (mitogen-activated protein kinase) pathway, has shown promising effects on B-raf-mutated and some RAS (rat sarcoma)-activated tumors in clinical trials. The objective of this study is to examine the efficacy of a novel allosteric MEK inhibitor RO4987655 in K-ras-mutated human tumor xenograft models using [(18)F] FDG-PET imaging and proteomics technology.

METHODS

[(18)F] FDG uptake was studied in human lung carcinoma xenografts from day 0 to day 9 of RO4987655 therapy using microPET Focus 120 (CTI Concorde Microsystems, Knoxville, TN, USA). The expression levels of GLUT1 and hexokinase 1 were examined using semi-quantitative fluorescent immunohistochemistry (fIHC). The in vivo effects of RO4987655 on MAPK/PI3K pathway components were assessed by reverse phase protein arrays (RPPA).

RESULTS

We have observed modest metabolic decreases in tumor [(18)F] FDG uptake after MEK inhibition by RO4987655 as early as 2 h post-treatment. The greatest [(18)F] FDG decreases were found on day 1, followed by a rebound in [(18)F] FDG uptake on day 3 in parallel with decreasing tumor volumes. Molecular analysis of the tumors by fIHC did not reveal statistically significant correlations of GLUT1 and hexokinase 1 expressions with the [(18)F] FDG changes. RPPA signaling response profiling revealed not only down-regulation of pERK1/2, pMKK4, and pmTOR on day 1 after RO4987655 treatment but also significant up-regulation of pMEK1/2, pMEK2, pC-RAF, and pAKT on day 3. The up-regulation of these markers is interpreted to be indicative of a reactivation of the MAPK and activation of the compensatory PI3K pathway, which can also explain the rebound in [(18)F] FDG uptake following MEK inhibition with RO4987655 in the K-ras-mutated human tumor xenografts.

CONCLUSIONS

We have performed the first preclinical evaluation of a new MEK inhibitor, RO4987655, using a combination of [(18)F] FDG-PET imaging and molecular proteomics. These results provide support for using preclinical [(18)F] FDG-PET imaging in early, non-invasive monitoring of the effects of MEK and perhaps other Ras/MAPK signaling pathway inhibitors, which should facilitate a wider implementation of clinical [(18)F] FDG-PET to optimize their clinical use.

Enhanced anti-tumor activity of the glycoengineered type II CD20 antibody obinutuzumab (GA101) in combination with chemotherapy in xenograft models of human lymphoma

Obinutuzumab (GA101) is a novel glycoengineered type II CD20 antibody in development for non-Hodgkin lymphoma. We compared the anti-tumor activity of obinutuzumab and rituximab in preclinical studies using subcutaneous Z138 and WSU-DLCL2 xenograft mouse models. Obinutuzumab and rituximab were assessed alone and in combination with bendamustine, fludarabine, chlorambucil, doxorubicin and cyclophosphamide/vincristine. Owing to strong single-agent efficacy in these models, suboptimal doses of obinutuzumab were applied to demonstrate a combination effect. Obinutuzumab plus bendamustine achieved superior tumor growth inhibition versus rituximab plus bendamustine and showed a statistically significant effect versus the respective single treatments. Combinations of obinutuzumab with fludarabine, chlorambucil or cyclophosphamide/vincristine demonstrated significantly superior activity to rituximab-based treatment. Obinutuzumab monotherapy was at least as effective as rituximab plus chemotherapy in vivo, and obinutuzumab plus chemotherapy was superior to the respective monotherapies. These data support further clinical investigation of obinutuzumab plus chemotherapy.

Determination of phosphorylated proteins in tissue specimens requires high-quality samples collected under stringent conditions

AIMS

For selection of patients who will benefit from targeted therapies, identification of biomarkers predictive of treatment response is desirable. Activation of the targeted pathway becomes apparent by protein phosphorylation. Determination of this phenomenon is therefore considered a promising biomarker approach. To date, however, it is unclear whether routinely collected tissue specimens allow determination of in-vivo phosphorylation states.

METHODS AND RESULTS

To investigate whether routinely collected tissue specimens retain the true phosphorylation states of a tumour's proteins, we compared protein phosphorylation states between matched tumour samples that were subjected to different ischaemic times by immunohistochemistry. The influence of formalin fixation and paraffin-embedding on phosphorylation states was investigated by comparison of matched fresh frozen and formalin-fixed paraffin-embedded surgical specimens as well as small biopsies. We show that ischaemia influences protein phosphorylation in a tumour-specific, unpredictable manner. Formalin fixation and paraffin-embedding lead to a decrease in detectable protein phosphorylation in larger surgical specimens, but not in small biopsies.

CONCLUSIONS

Determination of protein phosphorylation using routinely collected surgical specimens results in artefacts which do not reflect a tumour's true states of pathway activation. Valid measurement of phosphorylated biomarkers requires that tissue collection procedures are tightly controlled, avoiding ischaemia and large-specimen fixation.

Quantification of cell surface proteins with bispecific antibodies

Flow cytometry is an established method for fast and accurate quantitation of cellular protein levels and requires fluorescently labeled antibodies as well as calibration standards. A critical step for quantitation remains the production of suitable detection antibodies with a precisely defined ratio of antigen-binding sites to fluorophores. Problems often arise as a consequence of inefficient and unspecific labeling which can influence antibody properties. In addition, the number of incorporated fluorophores necessitates a special normalization step for quantitation. To address these problems, we constructed different mono- and bivalent bispecific antibodies with binding site(s) for the cell surface antigens, cMET, EGFR1/HER1, ErbB2/HER2 or ErbB3/HER3 and with an additional digoxigenin-binding single-chain Fv fusion. The fluorophore Cy5 was covalently coupled to digoxigenin and quantitatively bound by the bispecific antibody. A panel of tumor cell lines was assessed under different culture conditions for absolute receptor expression levels of the indicated antigens and the data were set in relation to mRNA, gene count and immunoblot data. We could reproducibly quantify these receptors, omit the otherwise required normalization step and demonstrate the superiority of a 1 + 1 bispecific antibody. The same antibodies were also used to quantify the number of proteins in intracellular vesicles in confocal microscopy. The antibodies can be stored like regular antibodies and can be coupled with different digoxigenin-labeled fluorophores which makes them excellent tools for FACS and imaging-based experiments.

Methylnaltrexone for the treatment of opioid-induced constipation

Opioids are the drugs of choice for treating moderate-to-severe pain, especially for patients in the end stage of cancer or other advanced illnesses, and also in critical care or for the treatment of chronic pain. Side effects such as nausea, pruritus, dizziness and constipation have to be controlled in order to use these drugs to their full potential. Opioid-induced bowel syndrome and constipation caused by activation of μ-receptors in the gut can have such distressing effects that some patients prefer to forego adequate pain control. Methylnaltrexone is a μ-opioid receptor antagonist that, unlike naltrexone or naloxone, does not pass the blood-brain barrier, and therefore does not impair the centrally mediated analgesic effect of opioids. It is licensed for the treatment of opioid-induced constipation in palliative care in more than 50 countries. This article presents practically relevant pharmacological data, basic research results and evidence from clinical research about methylnaltrexone, and outlines potential future therapeutic options for this promising drug.

Abstract 3603: Identification of potential pharmacodynamic markers for HER3 targeted cancer treatment by a multi-technology approach

The implementation of pharmacodynamic (PD) markers in clinical drug development is becoming a key element for guiding or defining the optimal biological dose during Phase 1 dose escalation. In the past the main focus during Phase 1 was to define the maximum tolerated dose of a novel drug and the nature of its dose-limiting toxicity (DLT). Nowadays, in the context of personalized cancer treatment and in particular with well-tolerated antibody treatments, which often do not show any DLTs, PD markers are used to monitor drug target inhibition and the modulation of associated pathways. The correlation of PD effects with pharmacokinetics (PK) data can therefore guide the dose selection for further clinical development. Here we describe a hypothesis free approach using three different technology platforms to identify potential PD markers for HER3 targeted treatment in pre-clinical models. The technology platforms were selected to enable the evaluation of RNA, miRNA and protein expression in the respective tumor models. By looking at RNA and protein modulation in parallel the likelihood of identifying highly regulated signaling networks might increase significantly. Five different mouse xenograft models were treated once with 10 mg/kg of a glyco-engineered anti-HER3 antibody and tumors were explanted after 1 h, 24 h and 168 h post-treatment. In addition, tumors from vehicle-treated control animals were taken after 1 h and 168 h. Three out of five animal models are known to respond to anti-HER3 therapy whereas the other two do not respond. Tumor samples were analyzed for RNA and miRNA expression using Affymetrix arrays and protein expression by reverse phase array (MD Anderson Cancer Center). Data sets have been analyzed using biostatistics and bioinformatics. The focus was to look for global PD effects across xenograft models which are significantly modulated over time and are not seen in any vehicle control. In addition, we investigated PD markers which are dependent on the response status. Overall we saw that, independent of the technology used, the samples of each individual animal model cluster together. Based on our filter criteria we identified 19 candidate markers on the reverse phase array, 24 candidate genes within gene expression profiling and 19 using miRNA profiling, which are modulated after HER3 targeted treatment. Bioinformatics analysis revealed that some selected molecules are located downstream of HER3 thus suggesting a potential relevance within the HER3 signaling network and specifically RAS activity was altered due to anti-HER3 targeted treatment. Our goal was to compare PD signatures derived from RNA, miRNA and protein array analysis to comprehensively map molecular changes after targeted treatment. Nevertheless, it needs to be demonstrated that the molecular changes, which have been identified in our pre-clinical models, can be translated to clinics.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 3603. doi:1538-7445.AM2012-3603

Opioid-induced constipation in advanced illness: safety and efficacy of methylnaltrexone bromide

Constipation, one of the major side effects of opiates used in palliative care, can impair patients’ quality of life to a point where it prevents sufficient pain control. Methylnaltrexone is a novel μ-receptor antagonist, which does not pass the blood brain barrier. It is licensed to treat opiate induced constipation for patients with advanced diseases. This review article presents an overview of pharmacology and safety of its application, evidence of its efficacy and economic aspects of its use in clinical practice. Available data are limited but strongly suggest that methylnaltrexone causes laxation in less than 24 hours for at least half of those patients over the first two weeks of usage without impairing pain control or causing serious adverse effects. To avoid danger of gastrointestinal perforation it is contraindicated for patients at risk for that complication. More research is needed to evaluate its long-term efficacy and economic impact.

Influence of a Capping Layer on the Mechanical Properties of Copper Films

The substrate curvature technique was employed to study the mechanical properties of 0.6 μm and 1.0 μm Cu films capped with a 50 nm thick Si3N4 layer and to compare them with the mechanical properties of uncapped Cu films. The microstructures of these films were also investigated. Grain growth, diffusional creep and dislocation processes are impeded by the cap layer. This is evident in the form of high stresses at high temperatures on heating and at low temperatures on cooling. At intermediate temperatures on heating and cooling, stress plateaus a relatively low stresses exist. This can be explained by the so-called Bauschinger effect. A film thickness dependence of the stresses in the film could not be observed for capped Cu films.

Observation and Modelling of Electromigration-Induced Void growth in Al-Based Interconnects

Accelerated electromigation tests on unpassivated, pure aluminum interconnects were performed. The failure mechanisms were observed by interrupting the tests and exanming the conductor lines using an SEM. Because the metal thin film was subjected to a so-called laser reflow process before patterning, grain boundaries were visible in the SEM as thermal grooves. Voids were observed to move along the line and to grow in a transgranular manner, and a characteristic asymmetric void shape was identified which seems to be related to the failure mechanism. It is argued that substantial progress in modelling and understanding of electromigration failure can be made by consideration of such void shape effects.

Influence of Film Thickness and Capping Layer on the Mechanical Properties of Copper Films

Substrate curvature and X-ray technique were used to study the mechanical properties of Cu films. Stress-temperature curves were measured using both methods. An additional analysis of the X-ray peak width allows us to estimate grain size and dislocation density as a function of temperature. It can be shown that a capping layer changes the mechanical properties of a Cu film strongly and that in capped films dislocation processes seem to be more important than diffusion at high temperatures.

Measurement of Thermally-Induced Strains in Polycrystalline Al Thin Films on Si Using Convergent Beam Electron Diffraction

Strains in polycrystalline Al films grown on oxidized Si wafers were measured using convergent beam electron diffraction (CBED). CBED patterns were acquired on a Zeiss EM 912 TEM equipped with an imaging energy filter and CCD camera. HOLZ line positions in the (000) CBED disk were matched using an automated refinement procedure. A sensitivity to variations in lattice parameter of approximately 0.00007 nm was obtained. Strong deviations from a simple equibiaxial strain, perfect [111] texture model were observed.

Observation and Modelling of Electromigration-Induced Void Growth In AI-Based Interconnects

Accelerated electromigation tests on unpassivated, pure aluminum interconnects were performed. The failure mechanisms were observed by interrupting the tests and examining the conductor lines using an SEM. Because the metal thin film was subjected to a so-called laser reflow process before patterning, grain boundaries were visible in the SEM as thermal grooves. Voids were observed to move along the line and to grow in a transgranular manner, and a characteristic asymmetric void shape was identified which seems to be related to the failure mechanism. It is argued that substantial progress in modelling and understanding of electromigration failure can be made by consideration of such void shape effects.

A new acylated flavone glycoside from the fruits of Stocksia brauhica

Phytochemical investigations of the fruits of Stocksia brauhica (Sapindaceae) resulted in the isolation of a new acylated flavone glycoside. Its structure of the new compound brauhenefloroside D (1) was established as 3-O-[(alpha-L-rhamnopyranosyl)oxy]-7-O-[(acetyl)-beta-D-glucopyranosyl (1 --> 4)]-[6-O-(4-hydroxy-E-cinnamoyl)-beta-D-glucopyranosyl-(1 --> 2)-alpha-L-rhamnopyranosyl)-oxy]-kaempferol. The structure elucidation of the new compound was based primarily on 1D and 2D NMR analysis, including COSY, HMBC and HMQC correlations.

Analysis of bacteria by pyrolysis gas chromatography–differential mobility spectrometry and isolation of chemical components with a dependence on growth temperature

Pyrolysis gas chromatography-differential mobility spectrometry (py-GC-DMS) analysis of E. coli, P. aeruginosa, S. warneri and M. luteus, grown at temperatures of 23, 30, and 37 degrees C, provided data sets of ion intensity, retention time, and compensation voltage for principal component analysis. Misaligned chromatographic axes were treated using piecewise alignment, the impact on the degree of class separation (DCS) of clusters was minor. The DCS, however, was improved between 21 to 527% by analysis of variance with Fisher ratios to remove chemical components independent of growth temperature. The temperature dependent components comprised 84% of all peaks in the py-GC-DMS analysis of E. coli and were attributed to the pyrolytic decomposition of proteins rather than lipids, as anticipated. Components were also isolated in other bacteria at differing amounts: 41% for M. luteus, 14% for P. aeruginosa, and 4% for S. warneri, and differing patterns suggested characteristic dependence on temperature of growth for these bacteria. These components are anticipated to have masses from 100 to 200 Da by inference from differential mobility spectra.

The effect of membrane potential on the development of chemical osmotic pressure in compacted clay

When clay soils are subjected to salt concentration gradients, various interrelated processes come into play. It is known that chemical osmosis induces a water flow and that a membrane potential difference develops that counteracts diffusive flow of solutes and osmotic flow of water. In this paper, we present the results of experiments on the influence of membrane potential on chemical osmotic flow and diffusion of solutes and we show how we are able to derive the membrane potential value from theory. Moreover, the simultaneous development of water pressure, salt concentration and membrane potential difference are simulated using a model for combined chemico-electroosmosis in clays. A new method for short-circuiting the clay sample is employed to assess the influence of electrical effects on flow of water and transport of solutes.

p73alpha is a candidate effector in the p53 independent apoptosis pathway of cisplatin damaged primary murine colonocytes

AIMS

Colonocytes were derived from wild-type (wt) and p53 deficient mice to investigate p53 dependent and independent death pathways after cisplatin treatment, and the role of p53 in growth regulation of primary, untransformed epithelial cells.

METHODS

Wt and p53 null colonocytes were exposed to cisplatin and DNA synthesis, apoptosis, and p53, p21, and p73 expression were investigated after six, 12, and 24 hours. Major p73 isoforms were identified by reverse transcription polymerase chain reaction (RT-PCR).

RESULTS

Cisplatin treated wt cells exhibited cell cycle arrest, whereas p53 null cells continued to synthesise DNA, although both cell types died. Apoptosis was significantly higher in cisplatin treated wt and p53 null colonocytes than in controls at all timepoints, although apoptosis was lower in cisplatin treated p53 null colonocytes than in wt cells. p53 expression was upregulated in cisplatin treated wt colonocytes. p21 expression was high and remained unchanged in cisplatin treated wt cells, although it was reduced in the absence of p53. p73 was investigated because it could account for p53 independent p21 expression and p53 independent death. RT-PCR detected full length p73alpha. p73 transcript levels remained unchanged, whereas p73 protein accumulated in the nucleus of cisplatin treated cells, irrespective of genotype.

CONCLUSIONS

p53 is essential for cell cycle arrest, but not apoptosis in primary murine colonocytes. Apoptosis is reduced in cisplatin treated p53 null cells. Nuclear accumulation of endogenous p73 after cisplatin treatment suggests a proapoptotic role for p73alpha in the absence of p53 and collaboration with p53 in wt colonocytes.

Evaluation for synergistic suppression of T cell responses to minor histocompatibility antigens by chloroquine in combination with tacrolimus and a rapamycin derivative, SDZ-RAD

The 4-aminoquinolines, chloroquine and hydroxychloroquine, can suppress chronic graft-versus-host disease (GVHD) following blood and marrow transplantation (BMT) in mice and humans, respectively. We hypothesized that chloroquine in combination with tacrolimus and the rapamycin derivative SDZ-RAD can synergistically suppress T cell responses and antigen-presenting cell (APC) function in vitro. We used the APC-dependent C57BL/6 anti-BALB.B T cell response and APC-independent anti-CD3epsilon antibody-induced response to evaluate the role of synergism between chloroquine and tacrolimus or SDZ-RAD on each component of a T cell response to minor histocompatibility antigens. We found that chloroquine with tacrolimus had a greater synergistic suppression of APC-dependent compared to the APC-independent T cell responses, with a combination index (CIx) for 50% inhibition by mean effect analysis of 0.16 and 0.50, respectively (a lower number indicates greater suppression). By contrast, chloroquine with SDZ-RAD had a similar CIx between the two responsed 0.50 vs0.45) suggesting only T cell suppression. Synergy between chloroquine and SDZ-RAD involved a direct effect on T cell cytokine production, whereas synergism between chloroquine and tacrolimus was due to an effect on both T cells and APCs. We conclude that the renal-sparing 4-aminoquinolines may be used syneristically with immunosuppressive drugs currently used for BMT.

Cyclin D1 overexpression in colorectal carcinoma in vivo is dependent on beta-catenin protein dysregulation, but not k-ras mutation

Cyclin D1 protein overexpression is commonly found in colorectal carcinomas (CRCs) and is associated with a poorer prognosis, but the mechanism underlying overexpression remains uncertain. Both dysregulation of beta-catenin protein expression and k-ras mutation have recently been shown to promote cyclin D1 expression in human in vitro and rodent in vivo studies. In this study, 53 sporadic CRCs were examined by immunohistochemistry for cyclin D1 and beta-catenin protein expression, and with PCR and direct DNA sequencing for k-ras gene status. The study also addressed whether cyclin Dl overexpression might associate with poorer prognosis because of a relationship with poorer response to 5-fluorouracil (5FU) chemotherapy. Cyclin D1 overexpression was demonstrated in 34/53 (64%) CRCs, was significantly associated with higher Dukes' stage, and was particularly prominent at the invasive edges of carcinomas. Furthermore, cyclin D1 overexpression was always and only seen in association with nuclear expression of beta-catenin. There were no significant associations between cyclin D1 overexpression and k-ras mutation or response to 5FU. Amongst 17 microsatellite unstable CRCs, a smaller proportion of tumours showed cyclin D1 overexpression (18%), but again cyclin D1 overexpression was only seen in cases showing nuclear beta-catenin expression. In conclusion, beta-catenin protein dysregulation, but not k-ras mutation, appears to be required for cyclin D1 overexpression in colorectal carcinoma in vivo.

Epigenetic inactivation of RASSF1A in lung and breast cancers and malignant phenotype suppression

BACKGROUND

The recently identified RASSF1 locus is located within a 120-kilobase region of chromosome 3p21.3 that frequently undergoes allele loss in lung and breast cancers. We explored the hypothesis that RASSF1 encodes a tumor suppressor gene for lung and breast cancers.

METHODS

We assessed expression of two RASSF1 gene products, RASSF1A and RASSF1C, and the methylation status of their respective promoters in 27 non-small-cell lung cancer (NSCLC) cell lines, in 107 resected NSCLCs, in 47 small-cell lung cancer (SCLC) cell lines, in 22 breast cancer cell lines, in 39 resected breast cancers, in 104 nonmalignant lung samples, and in three breast and lung epithelial cultures. We also transfected a lung cancer cell line that lacks RASSF1A expression with vectors containing RASSF1A complementary DNA to determine whether exogenous expression of RASSF1A would affect in vitro growth and in vivo tumorigenicity of this cell line. All statistical tests were two-sided.

RESULTS

RASSF1A messenger RNA was expressed in nonmalignant epithelial cultures but not in 100% of the SCLC, in 65% of the NSCLC, or in 60% of the breast cancer lines. By contrast, RASSF1C was expressed in all nonmalignant cell cultures and in nearly all cancer cell lines. RASSF1A promoter hypermethylation was detected in 100% of SCLC, in 63% of NSCLC, in 64% of breast cancer lines, in 30% of primary NSCLCs, and in 49% of primary breast tumors but in none of the nonmalignant lung tissues. RASSF1A promoter hypermethylation in resected NSCLCs was associated with impaired patient survival (P =.046). Exogenous expression of RASSF1A in a cell line lacking expression decreased in vitro colony formation and in vivo tumorigenicity.

CONCLUSION

RASSF1A is a potential tumor suppressor gene that undergoes epigenetic inactivation in lung and breast cancers through hypermethylation of its promoter region.